Field of the Invention
The present invention relates to a light source device.
Description of the Related Art
As a backlight device for a liquid crystal display apparatus, there has been proposed a light source device including B-LEDs and a wavelength conversion member including R fluorescent bodies and G fluorescent bodies. The B-LEDs are light emitting diodes (LEDs) that emit blue light. The R fluorescent bodies are fluorescent bodies excited by the blue light to emit red light. The G fluorescent bodies are fluorescent bodies excited by the blue light to emit green light. In such a light source device, the red light is emitted from the R fluorescent bodies and the green light is emitted from the G fluorescent bodies by the blue light from the B-LEDs. Combined light obtained by combining the blue light from the B-LEDs, the red light from the R fluorescent bodies, and the green light from the G fluorescent bodies is emitted from the light source device. If such a light source device is used, it is possible to obtain light in a wide color gamut as light emitted from the light source device.
In recent years, a quantum dot has been proposed as a fluorescent body (a wavelength conversion element) that can generate light having high purity by being excited. The quantum dot is a fluorescent body that reacts to ultraviolet light or blue light to emit light having a wavelength corresponding to a particle diameter of the quantum dot. If the quantum dot is used, it is possible to obtain red light and green light having half-value width of approximately 40 nm from blue light. Therefore, it is possible to obtain light in a wider gamut as light emitted from a light source device.
A light source device including the quantum dot is disclosed in, for example, Japanese Patent Application Laid-open No. 2012-022028. In a technique disclosed in Japanese Patent Application Laid-open No. 2012-022028, a sheet member (a quantum dot sheet) containing quantum dots are used as wavelength conversion members. Backlights including such a quantum dot sheet are also increasing.
Japanese Patent Application Laid-open No. 2013-218954 discloses a technique for suppressing color unevenness at the time when a quantum dot member is provided between a light source of an edge-type backlight and a light guide plate. Specifically, there is disclosed a light source device including an optical component having a light incident surface opposite a plurality of light sources and a color unevenness preventing structure that suppresses lights of the light sources from being directly made incident on the optical component.
Japanese Patent Application Laid-open No. 2011-171365 discloses a light source device in which a light blocking unit that blocks at least a part of light directed to a direction of an angle equal to or larger than an irradiation angle of a translucent member covering a light source and directed to a light incident surface is provided.